The Wister Mud Pot Lineament: Southeastward Extension or Abandoned Strand of the San Andreas Fault?

We present the results of a survey of mud pots in the Wister Unit of the Imperial Wildlife Area. Thirty-three mud pots, pot clusters, or related geothermal vents (hundreds of pots in all) were identified, and most were found to cluster along a northwest-trending line that is more or less coincident with the postulated Sand Hills fault. An extrapolation of the trace of the San Andreas fault southeastward from its accepted terminus north of Bombay Beach very nearly coincides with the mud pot lineament and may represent a surface manifestation of the San Andreas fault southeast of the Salton Sea. Additionally, a recent survey of vents near Mullet Island in the Salton Sea revealed eight areas along a northwest-striking line where gas was bubbling up through the water and in two cases hot mud and water were being violently ejected

The 10 micron spectral structure in comets

The 10 micron spectra of comets Halley (1982i), Wilson (1986l), Kohoutek (1973f) and Bradfield (1987s) are presented and compared. The silicate emission profiles of Halley and Bradfield are seen to be remarkably similar in that both contain a sharp break in the spectrum at 11.3 microns. Comet Bradfield does not show the same double peak structure seen in olivine and reported in Comet Halley be Campins and Ryan (1988) and Bregman, et al. (1987). The authors interpret the 11.3 micron signature as being due to olivine-type dust grains with at least some degree of crystallinity. Olivine alone is not enough to reproduce the shape of the 10 micron structure. However, in view of the authors' past success in fitting interstellar dust features with the emissivity profile obtained from amorphous grains produced by laser-vaporizing olivine, this is a very appealing identification. They note that there are significant variations in olivine spectra due to compositional differences, grain size distribution and related grain temperature variations to make the olivine identification tentative. They further tentatively identify the 9.8 micron feature in Halley as being due to either amorphorous olivine or a phyllosilicate (layer lattice). Neither the spectra of Halley, Kohoutek, nor Bradfield exhibited the 12.2 micron feature seen in Comet Wilson, which may prove diagnostic of the composition or thermal history differences between these comets. IR spectra of various mineral samples are discussed in terms of their match to cometary spectra

How Investors Interpret Past Fund Returns

The literature documents a convex relation between past returns and fund flows of mutual funds. We show this to be consistent with fund incentives, because funds discard exactly those strategies which underperform. Past returns tell less about the future performance of funds which discard, so flows are less sensitive to them when they are poor. Our model predicts that strategy changes only occur after bad performance, and that bad performers who change strategy have dollar flow and future performance that are less sensitive to current performance than those that do not. Empirical tests support both predictions

Glitter and Glints on Water

We present new observations of glitter and glints using short and long time exposure photographs and high frame rate videos. Using the sun and moon as light sources to illuminate the ocean and laboratory water basins, we found that (1) most glitter takes place on capillary waves rather than on gravity waves, (2) certain aspects of glitter morphology depend on the presence or absence of thin clouds between the light source and the water, and (3) bent glitter paths are caused by asymmetric wave slope distributions We present computer simulations that are able to reproduce the observations and make predictions about the brightness, polarization, and morphology of glitter and glints. We demonstrate that the optical catastrophe represented by creation and annihilation of a glint can be understood using both ray optics and diffraction theory. (C) 2011 Optical Society of Americ

Delegated Monitoring of Fund Managers

Because a money manager learns more about her skill from her management experience than outsiders can learn from her realized returns, she expects inefficiency in future contracts that condition exclusively on realized returns. A fund family that learns what the manager learns can reduce this inefficiency cost if the family is large enough. The family’s incentive is to retain any given manager regardless of her skill but, when the family has enough managers, it adds value by boosting the credibility of its retentions through the firing of others. In this way, large fund families add value through crosSC-sectional reputation. As the number of managers grows the efficiency loss goes to zero

FUND FAMILIES AS DELEGATED MONITORS OF MONEY MANAGERS

Because a money manager learns more about her skill from her management experience than outsiders can learn from her realized returns, she expects inefficiency in future contracts that condition exclusively on realized returns. A fund family that learns what the manager learns can reduce this inefficiency cost if the family is large enough. The family’s incentive is to retain any given manager regardless of her skill but, when the family has enough managers, it adds value by boosting the credibility of its retentions through the firing of others. As the number of managers grows the efficiency loss goes to zero

Silicate Emission in the TW Hydrae Association

The TW Hydrae Association is the nearest young stellar association. Among its members are HD 98800, HR 4796A, and TW Hydrae itself, the nearest known classical T Tauri star. We have observed these three stars spectroscopically between 3 and 13 microns. In TW Hya the spectrum shows a silicate emission feature that is similar to many other young stars with protostellar disks. The 11.2 micron feature indicative of significant amounts of crystalline olivine is not as strong as in some young stars and solar system comets. In HR 4796A, the thermal emission in the silicate feature is very weak, suggesting little in the way of (small silicate) grains near the star. The silicate band of HD 98800 (observed by us but also reported by Sylvester and Skinner (1996)) is intermediate in strength between TW Hya and HR 4796.Comment: 22 pages, 11 figures, LaTeX2e and AAS LaTeX macros v5.0. Accepted for publication in A

Comment on 'Non-equilibrium thermodynamics of light absorption'

A recent paper by Meszéna and Westerhoff (1999 J. Phys. A: Math. Gen. 32 301) has aimed to address what is referred to as a principal question of biological thermodynamics, the possibility of describing photosynthesis in terms of non-equilibrium thermodynamics. The issue is associated with a misrepresentation of the fundamental photophysics involved, and as a result the analysis is invalid

Some 5-13 micrometer airborne observations of Comet Wilson 1986l: Preliminary results

Comet Wilson was observed from the Kuiper Airborne Observatory approximately 23.6 and 25.7 Apr. 1987, UT (approx. 3 to 5 days after perihelion) using the NASA-Ames Faint Object Grating Spectrometer. Spectrophotometric data were observed with a 21 inch aperture between 5 and 13 micrometer and with a spectral resolution of 50 to 100. Spectra of the inner coma and nucleus reveal a fairly smooth continuum with little evidence of silicate emission. The 5 to 8 micrometer color temperature of the comet was 300 + or - 15 K, approx. 15 percent higher than the equilibrium blackbody temperature. All three spectra of the nucleus show a new emission feature at approx. 12.25 micrometer approx. two channels (.22 micrometer) wide. Visual and photographic observations made during the time of these observations showed a broad faint, possible two component tail. No outburst activity was observed

Mutual Fund Survivorship

This article provides a comprehensive study of survivorship issues using the mutual fund data of Carhart (1997). We demonstrate theoretically that when survival depends on multiperiod performance, the survivorship bias in average performance typically increases with the sample length. This is empirically relevant because evidence suggests a multiyear survival rule for U.S. mutual funds. In the data we find the annual bias increases from 0.07% for 1-year samples to 1% for samples longer than 15 years. We find that survivor conditioning weakens evidence of performance persistence. Finally, we explain how survivor conditioning affects the relation between performance and fund characteristics